Coyote biology key to effective trapping, hunting
[Reprinted from original]
Coyotes are an elusive and challenging predator, especially for cattlemen. But beyond the sharp howls and missing calves, coyotes are cunning canines that make population control much more complex than point and shoot methods can mitigate.
At a Kansas State University Extension program in Columbus, Kansas last week, K-State Wildlife Specialist, Drew Ricketts emphasized the importance of knowing your enemy for coyote control.
“The philosophy behind learning coyote biology is to understand behavior and social structure when we’re trapping,” Ricketts said. “Over the last 200 years, the range of the coyote has expanded greatly to cover almost all of North America with 19 sub-species of coyote represented across the continent.”
Coyotes with well-furred, pale bellies and light pelts are traditionally the most marketable from a trapping and fur sales standpoint, but subspecies come in a wide variety of other shades from dark browns and black to red tinged pelts.
“Since the fur market crashed in 1987, coyote numbers have steadily increased,” Ricketts said. “The fur market is very linked to the global economy and now the majority of fur harvested in the United States goes to Greece, Russia and China.”
Today, in Kansas, coyotes have almost no natural predators, leaving their population somewhat out of control.
“We don’t have wolves around so anywhere from 40% to 90% of mortality in coyotes can be attributed to human causes,” Ricketts said. “In my collared study we had seven mortalities in two years — three were killed in vehicle collisions on interstate 70, two were shot at the same ranch a few months apart and two dies of disease.”
While humans are one environmental control for coyote populations, their ability to control the growth cycle is largely limited by biology. And, one of the most challenging facets of coyote biology to overcome is the animal’s quick response to environmental changes.
“Coyotes have the ability to perform what we call compensatory natality,” Ricketts said. “If there are a lot of food resources relative to the number of coyotes, then they can increase their litter size.”
A typical coyote litter in lean years would number around three pups, but in years with plenty of food, shelter and water, litter numbers would be eight and up on average. Without legal means to limit the overall population, coyote control mostly comes down to understanding travel patterns and limiting problem individuals.
“We can get rid of individuals that are causing problems, but it’s really hard to effect overall population numbers,” Ricketts said. “If we kill larger numbers it creates a surplus of food, which then doubles litter size the following year.”
For coyotes, family groups typically consist of just one male, one females, their pups and perhaps one or two pups from the previous year’s litter who stuck around to help take care of the younger siblings. These groups establish a home range where they have easy access to the necessary resources.
“Home range size can vary from one square mile up to 55 miles,” Ricketts said. “Some coyotes use a small amount of area while others cover a wide range.”
The average home range size in Kansas is around 750 acres for females and 800 acres for males, a number that goes up slightly for transient males and females without a family group.
Transient individuals make up close to 47% of the total coyote population and move between ranges on the outskirts and cover a wider area to be ready to step in to family groups when either the male or female dies. Some transient individuals are young, teenage-maturity pups that haven’t established their own home range yet and others are long-term transients.
“A transient female has to hunt a lot more to find the resources she needs at different times of the year than an established family group,” Ricketts said. “It makes transient individuals easier to catch than the residents that are raising pups.”
In Ricketts’ studies, transient individuals were frequently pulled to new ranges by the scent of decaying animal remains. Individuals would sometimes travel as much as eight miles in one day to visit a carrion site.
The simplest way to keep coyotes away from property, Ricketts said, is to quickly remove any dead livestock. Overall control of statewide populations is a much more difficult goal to achieve.
“They have done some advanced modeling in these studies that suggests you would have to eradicate 70% of the coyote population every year for 50 years in order to come close to eradicating the species,” Ricketts said.